I'll second Daryl's question: are you sure this is gastroparesis? How was this diagnosed? Can you describe what happens? In true gastroparesis, it wouldn't matter what you ate; all foods would cause nausea and vomiting.
http://www.medterms.com/script/main...articlekey=8286
I'm wondering if you are perhaps referring to gastroenteritis instead? If eating lighter foods helps, it sounds more like gastroenteritis to me.
In a case of gastroenteritis (also known as gastritis), avoiding spicy foods, carbonated beverages and anything with caffeine is a must until the inflammation subsides. Broths, Jellos, clear liquids and lighter proteins such as fish and eggs may be better tolerated as would smaller, more frequent meals.